Irish lichens

Caloplaca ulcerosa

Order: Teloschistales       Family: Teloschistaceae

Species: Caloplaca ulcerosa

Growth type crustose
Photos: On deciduous tree trunk. Foynes, Co. Limerick, Ireland
Identification needs confirming

Thin grey-white thallus with pale yellowish-green soredia from blister-like craters. Soralia initially scattered but often become confluent. Scattered apothecia with orange discs, margins narrow. Spores 8-12 x 4-8 Ám, septum 3-6 Ám wide. Paraphyses with swollen tips. Apothecia and soredia K+ red

Infrequent on nutrient-enriched mature trees in well-lit situations

Similar: Caloplaca obscurella has brownish discs, thallus becomes bright green when wet, apothecia and thallus K-

Caloplaca ulcerosa

Caloplaca ulcerosa
Caloplaca ulcerosa. September 2010

All images used are copyright. Please contact me if you find errors.